Carburetor system



Apri@ 2, 393i. c. E. HQFBAUER Y GARBURETOR SYSTEM Filed Sept. 4 1926 Owww WV. nu i A. L.. u r

Ob l n 19.6 c

5 accordance with the requlrement of such con- Patented Apr., 2S, @Si

isozo GASPAR E HDFBAUER, F NEW YORK, N. Y., ASSIGNOR TO POUNT CARBURETORCRFOTION, 0E' NEW YGRK, N. Y., A CORPORATION 0F NEW YQRK cuanron sxsfrmaApplication filed September 4, 1926. Serial No. 133,578.

My invention generally relates to an arrangement where y a mixture ofair and gas having a yconstantratio is supplied to the engineunderallrunnin conditions and in ditions and in oneof its phases, relates to anarrangement whereby the variation in the fuel level' of the tankincident to gas consumption or to operating conditions is elimi- 1nated'as a variant factor in the fuel feed.

In another of its phases,- my inventions relates to a carbureting systemand has particular reference to means for supplying fuel for internalcombustion engines and co-ordi' 5 nately. involves -an arrangementwhereby fuel normally positioned at a low level isautomatically fed tothe point of combustion in accordance with the requirements of theengine operation, ,and during its passage 2' thereto is converted into acombustible mixbe `understoodthat this ture of fuel and air, and morearticularly relates to a carbureting system o the character set forth inwhich the variation of the liquid level in the fuel tank is eliminatedasa variantvfactor of the carbureting system.

'While I will herein describe and illustrate the first-mentioned hase ofmy invention as associated with an incorporated as part of my novelvfuel feeding system because it serves markedly to improve the feedingof fuel under' the conditions and circumstances andin the manner hereindisclosed, it will hase serves a much wider field of utility, an that asto its broaderV features, the disclosure of a compensati# ving deviceofthecharacterherein described in connection with my fuel feeding systemis to be interpreted merely as illustrative of one of its applicationsfand not as limitative unless otherwise specifically set forth intheclaims. Y f

' In a fuel feeding system, 4for example, of the character hereinillustrated, one of the factors aecting the feed of fuel from a tank,particularly from-a tank at a. low level, 1s the change in the fuellevel incident not only 'to running conditions, but also to-:lowering ofthe level Ias the fuelis consumed ;,and one of the importantobjectsv ofmyinvention isfthe provisionof an arrangement whereby the effect of thework done in lifting the fuel from the tank is uniform regardless of thevarying distances the fuel has to be lifted as the fuel level changes ordrops.

As to the carbureting system'y herein disv515 closed, the How induced bythe induction in the intake manifold is proportioned between air andfuel so that a mixture is produced which will move from a point of fuelsupply,

which may be at a lower level, and a feature of the operation of my fuelsupply system is such that the diminished pressure head resulting fromthe minimum induction in the intake manifold at operating conditions ofan automobile engine Will form what I term a primary mixture capable ofretaining 'its characteristics due to a partial mixture therewith in themanner to be set forth of a quantity of air also initially induced bythe pres- 7 sure in the intake manifold.

In the embodiment of the invention herein disclosed wherein conditionsexist so that the rate of iiow induced by the intake manifold is that ofthe speed of varying operating conditions, the parts of my system are soarranged and constructed that this primary mixture contains a pro ortionof fuel and air which falls short of) forming a mixture adaptablefornormal engine operation, but contains a suilicient alr content tomaintain the fuel in its pre-determined condition of comm-inution andvaporization during :its traverse from the point of initial admixture tothe point -of predetermined modification to f provide the-most eiiicientoperating mixture. 35

Another feature of the operation ofthe apparatus herein disclosedcomprises anarrangement whereby the inductive eifect :of

themanifold intake is proportioned as between air and fuel so that itcausesnot only a flow of theprimary mixture but also an admixture ofadditional air therewith so as to change the primary mixture to a; moreAperfect combustible charge, and with an increase in the inductiveeffect above the minimum there will be ani acceleration in the. flow ofboth the primary mixture andthe additional air,-so proportioned andrelatedjas-,to produce a correctly proportioned mixturesuit- I able forand responsive to all running condi-- 10 tions. In the specic embodimenthereinA disclosed, this arrangement is such that with the accelerationin flow of the primary mixture, in accordance with the variations in therunning conditions and with its modilication to a more efficientlycombustible charge by increasing the ratio of air to fuel, the mixtureso formed will be automatically predetermined as to the ratio of the airto the fuel, and will be supplied in accordance with runningrequirements.

Further features of my apparatus include the construction andarrangement of parts to control the air flowing toward an enginecylinder, to proportionately meter the air and cause the air to receiveand become mixed with the amount of fuel it can support, means beingprovided to cause a proportioning of air to fuel or air to a fuelmixture under all conditions. These conditions include those involving apulsating flow and those which involve rapid changes in the rate of flowas a change fromlow speeds to high speeds and vice versa. The mixture isfree from the defects normally encountered due to the inertia of eitherany moving parts controlling the ratio of air to fuel or of portions ofa fuel mixture.

My invention further contemplates the provision of apparatus which willproportion the flow induced bythe intake manifold as between an airsupply and fuel, or an air supply and a fuel mixture and in thecombination therewith of means for attaining such admixture, comprisingfuel mixing means, which eliminates the inertia due to movement ofaliquid fuel, the parts being so constructed and arranged that the 'airstream and the fuel mixture stream are responsive without material andrelative la between them to produce an explosive com ustion mixtureunder all conditions normally encountered in an automobile engine.

An important object of the invention is the provision of means forautomatically modifying the primary mixture so as to provide aproportioning of air and fuel under all working conditions, which givesmaximum results.

Another important object of the invention is the provision of meanswhich automatical? ly modifies the primary mixture and at the same time`automatically controls the quantity thereof in correct proportion, thusproducing a substantially correct final mixture.

Still further, more specific embodiments of my invention contemplate theprovision in a carbureting system of a primary fuel.

supply and of means to correct the mixture so formed including an aircontrol automatically variable, in accordance with requirements, therebeing combined therewith additional means to accelerate the supply offuel when an instantaneous full thrpttle opening is made.

In the specific embodiment of m invention, illustrated in the drawings,t eparts of my carbureting system are so constructed `manifold may beproportioned between the fuel mixture and air without material andrelative lag in responsiveness of the supply.

For eliminating the variations or changes in the fluid level in the tankas a varying factor, so as to provide for a constant and uniform levelin the fuel fed therefrom under predetermined suction conditions, I haveillustrated in connection with the carbureting system above referred to,the provision whereby not only is the fuel fed from what is in fact, aconstant level, but the fuel is fed to the engine under a constantreduced pressure head regardless of the pressure conditions present inmy system and incident to the operation of the engine.

As one of the objects of my invention is to provide for this, withoutany necessity of in any way modifyinv the standard fuel tank with whichautomo iles are supplie(l,it is an object of my invention to positionthis arrangement exteriorly of the tank, and in accordance with theembodiment of my invention herein illustrated, this arrangementcomprises in a general way a member so arranged as to maintain on oneside thereof the pre'-y determined reduced pressure under which it isdesired that the fuel be fed tothe engine and on the other side, therequired suction lift necessary to lift the fuel from the tank. A

Although I have illustrated and shall describe my fuel feeding systemand level standardizing means as applied to internal combustion enginesof the character generally associated withan automobile, nevertheless itwill be understood that numerous phases and features of my inventionwill have a much larger field of utility, and it is not my intention tolimit myself to a use of this character. nor to -structural featureswhich are peculiar to or necessary for such an application. One of theimportant features of myinven tion resides in the fact that in theformation of the mixture incident to the lowered pressure head in theintake manifold, the correct proportioning of the air and the gas isprebriedy stated, are: the provision of an arrangement whereby thecontrol by amoving element is limited to the air factor in theproduction of an air fuel ratio; the provision of an arrangement wherebya primary mixture too rich to be employed for ordinary vehicle purposes,and of a substantially predetermined or fuel ratio is formed under allengine operating conditions; the provision of an arrangement whereby thecontrol of the air factor to convert the primary mixture into the finalmixture is operative under all engine operating conditions andautomatically responsive thereto; the provision of an arrangementwhereby the flow of fuel from the rear tank responsive to all engineoperating conditions is so automatically controlled as to eliminate thechanging level in the fuel tank as a variant and to give the effect of aconstant fuel tank level; the provision of an arrangement whereby themixture of the air in the gas is so controlled at the point of mixtureso as to cause the production of an intimate mixture of air with thefuel in the finely comminuted state.

The objects, generally, of my invention are to provide a carburetingsystem vwhich will be peculiarly eflicient wherein the character of themixture is maintained at maximum eiliciency at all running conditionsand the quantity of the mixture supplied for combustion purposes areautomatically controlled in a manner to give maximum operativeconditions with a minimum of waste and wherein the necessity forfrequent precise adjustments are absent, the apparatus comprisingrelativly simple parts, inexpensive to manufacture and assemble,necessitating no time consuming or expensive, accurate designing ormanufacture and extremely unlikely to be defective or mal-adjusted afteronce having been installed and operated;

For the attainment of the foregoing objects and such further objects asmay appear herein or be hereinafter pointed out, I make reference to theaccompanying drawing illustrating one form of my invention in which:

Figure 1 is a cross sectional elevation through the main elements of mycarbureting system, certain parts being omitted for the sake of clarityof illustration; -v

Figure 2 is a fragmentary cross sectional plan view taken on the line2-2 of Figure 1; and Figure 3 is a section taken in line 3-3 of Figure1.

lieferring to the drawings, and particularly to Figure 1, I have shownthe main elements of my system comprising a primary lifting and mixingdevice (portion A) Figure 1) and a secondary control vand mixingmechanism associated in relatively close proximity to and adjacent theengine (see portlon B, Figurel) and a'connecting-conduit-between theseportions of. the system.

Referring now to the portion A, it will be observed that I have shownthe fuel tank 11 with a supply of liquid fuel such as gasoline 13therein. Mounted within the tank and extending downwardly into the fuelis a pipe or conduit 14 open at the bottom and terminating short of thelowermost portion of the tank. This pipe 14 may be suitably mounted inthe tank by means of a flanged collar 15 or the like, to which the upperend of the pipe 14 is attached.

Referring now to the primary aspirating and mixing device A, oneembodiment contemplates the provision of an air intake element 24provided with a forwardly projecting nozzle 25, a portion of the outerwalls ofthe latter being externally threaded to engage within thelitting 29. It is contemplated that atmospheric air will enter into theelement 24 and will be drawn through the nozzle 25.

Although the detailed construction of the element 24 will be more orless optional, I illustrate it in the drawings as in the form of asubstantially cylindrical element having a number of openings 26 in itswalls and provided a-t its outer end with a. closure element 27.Preferably, I provide va tapering adjusting element 28 in the formusually found in a needle valve having bearing within the closurev 27,for movement along the axial line` thereof and which is adjustable byscrew threaded engagement for the purpose of establishing a means ofadjustment and control ofthe area within the nozzlefor purposes thatwill vmore fully be pointed out.

There is provided a separate fitting 29 having a bore therethrough whichcomprises two conical portions 30 and 31 converging towards the centralportion to a more restricted junction 32 which however presents aslightly smaller opening than the restricted dis-- charge 25.through theelement 25. The fitting 29 is suitably externally threaded atits v oneend so that one end thereof may make engagement with the element 24, andis also threaded externally at its .opposite end so that a suitableunion 33 may be made to engage over such threaded end of the fitting 29to establish connection between the latter and the main casing. It willbe observed that the lin lpart of the nozzle 25 and of the bore 31.

That conical portion of the venturi which is disposed toward the fitting25 is more abrupt yin angularity and shorter than the other portion 31which communicates with the lmain casing. It will be observed thatthenozzle 25 is so constructed as to be spaced from and project intothel conicallly" bored 'portion 30.-

It will vbe further observed that an annular chamber 34 is therebyproduced encircling the end of the nozzle and communicating with thespace between the constricted portion 25 of the nozzle and theconstricted portion 32 of the Venturi member 29.

Before proceeding with the more detailed description of the otherelements of the carbureting device, the operation of the primary liftingmeans and of the primary aspirating device will be elaborated. Theinvention contemplates the provision of a substantial suctionandflow'through the venturi. This flow not only draws air inwardlythrough the openings 26 and into and through the nozzle 25, but itserves to draw fuel in liquid condition up through the pipe 17 into theprimary mixing chamber.

The fuel level in the tank will vary not only with running conditions,but also will gradually be lowered as the fuel is consumed. The distancethe fuel has to be lifted will therefore vary, depending upon the tanklevel. The pressure or suction head, on the other hand, is dependentwholly upon the engine condition at the intake manifold. The fuel feedfrom the rear tank will therefore not be predetermined and uniform andone of the objects of my invention is the provision, which I will nowexplain, for eliminating this variation in the fuel level as a varianteffecting the feed of the fuel.

At C in Figure 1, I show a casing made up of two parts 35 and 36 betweenwhich is securely held a diaphragm 37 which may be made of silk treatedwith oil or with bakelite,

although it will be understood that while these materials are preferredby me, the use of these particular characters of materials is notessential to the operation of my carbureting system. The casing part 35is divided into two halves by the partition 37 having the passageway oropening 38 there through, thus forming two chambers 39 and 40 connectedby this passageway. The pipe 14 discharges into the upper chamber 39through the tube 40 to which it is locked by means of the nut 41. Thetube 40 in turn is threaded into the' opening 42 which leads into thechamber 39. The lower chamber 40 which is closed by the diaphragmy 37discharges through the opening 43 into the threaded mouth of the tube17.

A valve 45 controls the opening 38. Depending from the valve is'the stem46 which is locked to the top portion 47 ofthe diaphragm in anypreferred or desired manner. In the illustrated embodiment, I do this bynarrowing the stem as shown at 48 to provide the shoulder 49, the cutpart 48 of the diaphragm being received between the washer 50 below thisshoulder and' the widened annulus 51. Carried by the lower end of thestem is the pistonf52vmoving freely in the chamber 53 formed in thelower part of the casing 36, and open to the atmosphere so that thepiston is also opento the atmosphere.

The reduced ressure in the chamber 40 is predetermined y the amount ofsuction required to lift the valve 45 from. olf its seat and which, forexample, in an apparatus that I have constructed, is the suctionnecessary to lift gasoline 36". The pressure in the chamber 39 and inthe line to the ytank is predetermined b the suction lift required bythe level in the uid of the tank and any decrease in the How of thefluid in the line from the tank to the chamber 39 will tend to build upa pressure in the chamber 40 beyond that stated which will be broken bythe valve being lifted to a wider open position. The reverse conditionsWill be true where the level of the tank rises for any reasonwhatsoever. My carbureting system is so constructed and devised that itwill deliver a pressure under all opcrating conditions of the engine,which will be sullicient to maintain in the chamber 40 the constantpressure referred to which is sufficient to lift t-he gasoline from therear tank under the lowest possible tank level. By my system thereforethe fuel is lifted from the tank into the chamber 39 which thus becomesa constant level chamber and then is fed from this chamber in accordancewith engine requirements under the constant reduced pressure of thechamber 40. It will be understood of course that the system as a whole,is so arranged that it will operate to lift fuel from the tank under allpossible running conditions.

The fuel passing through the pipe 17 is then drawn to the restrictedopening 16 and into the chamber formed between the fittings 24 and 29.This chamber, as will be observed,

is so formed as to cause the fuel to take the form of a hollow inclinedannulus which is discharged into the venturi at the point 32 which isthe narrowest part of the venturi, and there meets with and isaccelerated by the flow of the column of a solid column of air throughthe nozzle 25. As a result of this arrangement, to which I apply theexpression primary lifting and aspirating means, not only is a mixtureof air and gas formed of a substantially uniform character, but the fuelis caused to assume a finely comminuted condition and to be mixed withthe air in a manner so as to form a stable primary mixture. The parts ofmy carbureting syste-m are so arranged and constructed that this primarymixture of air and gas is of a character too rich to be employed forordinary engine operation, and I will now proceed to describe the mannerin which this primary mixture is convert-ed into a mixture which isuniform as to its ratio of gas to air, and which is fed to the engine ata rate in accordance with engine requirements under all runningconditions. y

Referring now more particularly to the lea hand 'ruoli B, of Figui@1,'if wiii be observed t at the forward end ofthe Venturi fitting 31issuitably associated withand connected to a main casting-or member bybeing threaded into an internally threaded neck 61, integral with thecasting 60.

The neck 61 is so arranged with respect to the casting 60 as to directthe primary mix- `ture into an annular chamber similar to, but

larger than the primary mixing chamber 34, the mixture being'preferablylead into the annular chamber in a direction tangential to theperiphery. .(See Figure 2.) This chamber will be hereinafter referred toas the secondary mixing chamber, and constitutes a portion of thesecondary mixing or controlling device hereinbefore referred to tendingto perfect the mixture first formed.

The secondary mixing chamber is constituted by an upwardly disposedmember 62 mounted within an inwardly directed annular flange integralwiththe casting 60 and arranged slightly below the neck 61. The member62 tapers upwardly and is of a length preferably to completely'block thedirect path of the fuel mixture coming in through the neck 61. Withinthe upperportion of the casting 60, there is arranged a bushing orfitting 63 having a bore-which comprises two inwardly convergingportions 64 and 65 in a manner similar to the portions 30 and 31 of thefitting 29. The lower of these portions 64 is more steeply conical thanthe upper, and merges with the upper portion 65 at a constrictedjunction 66. The member 62 is designed and arranged to project slightlyinto 'and nest within the portion 64 and is shown in the drawings ashaving its discharge end smaller than and spaced from the constrictedpart 66, and arranged so as to discharge concentrically therethrough.Above the bushing 63,v the casting 60 is provided with a flange adaptedfor connection to the intake manifold of the engine in any of the numberof well-known ways; and within the upper portion of thevcasting 60, theusual throttle valve 71 is provided.

Before describing in detail the automatic operation of the elements,` itmay be explained that it appears that under all conditions of operationadditional air is drawn upwardly through the members 62 under controlledconditions by the suction produced within the intake manifold. This airattains a great velocity at the upper end ofthe member 62, and it willbe readil understood that the fuel mixture which as been caused to swirlaround the secondary mixing chamber will be picked up and directedupwardly through the fitting 63 along with this additional air enteringthrough member 62. Additional mixing and vaporizing will occur as themixture passes thorugh the constriction 66.

The controlling4 device comprises a conicalA @5 valve 67 normallyrestingby gravity upon and take-element 76 which is substantiallyl cylin-vdrical and is provided lwith openings 771for the admission of air. Theintake element .7 6

is considerably larger than the intake element 24, as are the openings77 with respect to the openings 26, and it will be understood that themain portion of the air necessary for the formation of4 a proper mixtureis supplied through the element 7 6.

The valve 67 is more or less controlled in its movement by the dash-potarrangement shown as carried below the element 76. More particularly, Iprefer to provide a chamber 80' adapted to contain liquid, and I haveshown the valve 67 provided with a downwardly projecting stem 81, thelatter being slidably mounted within a bearing portion .82 dependingfrom the lower wall 83 of the chamber 7 6. At its lower end, the stem 82is provided with a Vpiston 84 or the like, presen ting an increased areato the liquid whereby the movement of the valve 67 will be suitablyretarded and dampened.

- The dampening piston 84 has associated therewith a secondary piston 85in the form of a thin disc of large diameter and arranged to prevent agreater retarding surface and has a lost motion connection with the stem82 as follows: The secondary piston 85 is received in a reduced portionof the piston 84 so as to permit of a free limited movement of thesecondary piston 85. Spacing circular spurs or ridges 86 and 87 serve tohold the disc 85 away from contact with the primary piston 84. Theeffect of this two part damper is to provide a greater initialretardation of the upward movement of the valve 67, than on the downwardmovement tlieieof, because on the upward movement of the valve 67 thepistons 84 and 85 will move together from the time of initiation of suchmovement,

whereas on the downward movement of the valve 67, the stem 82 and thepiston 84 will move relatively to the piston 85 at the beginning of themovement.

The disc piston 85 as will be observed upon viewing Figure 3 of thedrawing has its inner edge so dimensioned and arranged as to iit looselyon thev piston 84 so as to provide a clearance between this edge and theadjacent wall of the piston. The outside edge ot` the piston 85 ishowever so arranged as to provide aY rather close it inside of the wallor skirt 116 of the chamber 80. Inside of the upper circular ridge 86,the piston 84 is provided with one or more openings 84', therethrough.

As a result of this arrangement, itwill be understood that not only isthe disc p iston 8.5 self-aligning and'galways true as to its positionin the chamber 8() but also upon theunsetting of the disc piston 85 fromits position lll() movement under the same character of impulse.

It is of course desirable that the starting mixture have an increasedrichness, and in order to control the continuation of this supply ofrelatively rich mixture, the valve 67 may e arranged and constructed topermit manual control thereof. For this purpose, I may employ a manuallycontrollable lever 100, the outer end of which may be operated by a lead101 of which a spring 102 forms a part from a suitable point on thedashboard so that it may be controlled. The inner end of the lever isarranged to engage the upper end of the valve 67. In this manner, whatamounts to an increased weight `may be given the valve.

Once the engine has started, the suction will immediately operate tolift the valve 67 olf of its seat. This lifting movement will beinitially retarded by the piston 84, and the amount of openin producedby the valve 47 will depend upon te speed of the engine. At any constantrate of speed, the valve 67 will iutter or oat at a predetermined point,to permit the admission of a predetermined amount of air through theopenings 77. It will be understood that the valve 67 will remain off itsseat in all conditions of engine operation.

It will therefore be seen that a vacuum will be serving to provide aprimary or basic, somewhat vaporous mixture throughout the running'period ofthe engine. The parts are so proportioned and arranged-thatthis initial mixture is richer than that required for normal automobileengine operation, and it will be observed that the secondary mixingchamber accomplishes the function, among other things, of reducing therichness of the mixture.

It will be further observed that the nal richness is controlled by theamount of air supplied through the openings 77 instead of by a needlevalve of the usual type which controls the amount of gasoline. Inasmuchas a suitable mixture comprises proportions of air and fuel in theneighborhood of 13 to 1, it will be obvious that the control of the 14factor instead of the 1 factor will render inaccuracies of design andmaladjustment of parts less effective in causing defective operation. Iconsider this an important feature of my invention. Another featurewhich I consider of great importance is the arrangement whereby fuelinsprayed or vaporized condition is picked up from an annular chamber byair passing throu h said chamber in an axial direction. This eature willbe clearly observed in connection with both the primary and secondarymixing chambers, and it will be obvious to those skilled in the art thatan arrangement of this character is fundamentally different from thatemployed in connection with the ordinary carburetor in that conditionsare attained wherein the flow induced by the intake manifold is moreaccu rately proportioned between air and fuel or air andfuel mixturebecause each agent is conditioned or prepared to be more readilyresponsive in supply.

A particular feature of the present invention resides in utilizinggasoline as the retarding liquid within the chamber 80. For thispurpose, a conduit 90 is made to communicate with the bottom of the neck61, the latter being enlarged so that a chamber 91 is provided whichwill collect any condensed excess vaporized fuel which may have reachedthis point. The conduit 90 communicates at its lower end with a chamber80 through the restricted passage 93.

A-particular advantage which is gained by utilizing gasoline as theretarding Huid lies inthe fact that this fluid may be utilized inmodifying the richness of the mixture 'at certain critical periods ofthe running of the engine. Thus, in the embodiment shown, I have shownthe valve 67 and its stem 81 as provided with a longitudinal boreorpassageway 94 opening through the valve 67 at its upper end. Thepassageway 94 communicates at its lower end through the transverseconnecting channel 95 with the interior of the chamber 96 formed betweenthe fixed lower end of the depending bearing 82 and the interior of thechamber 97 formed in the upper end of the piston 84. When the engine issuddenly accelerated, the valve 67 will tend to leap upward with acertain amount of suddenness. Normally, this would tend to produce amomentary unduly lean mixture. While a too sudden upward movement of thevalve is retarded by the piston 84 and plate 85, the richness requiredfor this quick acceleration is attained by me as follows: As the valve'moves upward quickly, a small amount of fuel is forced from thechamber96, through the passageway 94 and into the member 62. This temporarilyincreased richness is extremely advantageous inasmuch as it will benoted that this increase in richness occurs at exactly that period ofrunning when it is most needed, namely, during rapid or instantaneousacceleration. It will also be noted that this temporary raising ofadditional rich liquid fuel will be but moinentary. To overcome anytendency of forcing too rich a primary fuel throu h the passageway 94upon sudden acceleration, I show a passage 97 formed longitudinally ofthe valve 67 and concentric with, and exteriorlyv sudden rise of thevalve when the throttle is -mean to limit myself to the particularstructural features illustrated and described. Many changes in thedetails as herein described and illustrated may be made by those.skilled in the art without departing from the spirit and scope of theinvention as expressed in the appended claims. It is therefore intendedthat these details be interpreted as merely illustrative, and not in alimiting sense.`

The manner in which the fuel is fed by suction from the rear tank tothe, pipe 17 is such as to give the result of the suction always actingupon a constant liquid level regardless of the height of the fuel in therear tank.

The production of a satisfactory primary mixture is assisted materiallybythe manner in which the fuel feed from the pipe 17 directed sd as tochange the direction of the fuel feed from the pipe 17 and its.cO-action with the air column through 25 with the consequent beneficialresults in atomization, and

this is still further assisted by theprovision of a constriction 60 atthe terminal end of the pipe 17.

By the arrangement herein disclosed, I find that I attain a primarymixture in which the air and fuel are mixed together so as to provide amixture which not only is itself stable, but the sta-bility of which isstill further increased in its travel to the point of consumption.

. One of the important features pf my invention is an arrangementwhereby a fuel mixture of maximum eiiciency is at all times supplied forcombustion purposes,and the proportion of fuel and air contained therein1s maintained substantially constant regardless of running conditions,the proportion being such as to give the aforementioned maximumefficiency Another important feature of my invention is the employmentof a gravity valve such as that shown at 67 as the` main controllingfactor of the character of mixture to be produced because, not only doesit control, as already stated, the air which is the large factor of themixture, but a gravity valve presents a constant load regardless ofsuction conditions, and therefore moves exactly in accordance with and.proportional to the variation in such suction conditions.

The shape of the valve 67 which is herein illustrated as top-like incharacter, possesses features of advantage in so controlling anddirecting the flow of air as to cause it to serve its purposes withgreat eiciency in connection with the directing of the flow of air sothat a maximum mixing effect with the fuel mixture is produced. It willalso be observed that I herein show this valve 67 as positionedrelatively close to the constricted passageway through 61 and relativelyclose therefor to the point at which the primary fuel mixture isintroduced from the neck 61 which also I have found possesses featuresof advantage. K

In order to catch any liquid gasoline that may form above the valve 67,I have provided a space 110 adjacent the valve seat which vents abovethe throttle 71 by means of the tube 111 so that the gasoline settlingin this space 11() thus `works its way up into the pipe 111 and into thechamber.

Upon viewing the lower part Wall ofthe chamber 80, it will be observedthat there is a space 115 between the skirt 116 and the outer wall 117.ThereA is thus provided a clearance so as to eliminate any question ofactual `fitting and also to prevent warping or distorting of the partswhen they are assembled or disassembled, and to allow for errors inmanufacture.

I provide strainers 120 in the part C, and 121 in the part A for thewell-understood purposes which strainers serve in Ythis .relationship.

Having thus described my invention and,

illustrated its use, what I claim as new and desire to secure by LettersPatent is:

1. In a fuel feeding system arranged to supply' fuel from a storage tankpositioned at a distance from an internal combustion engine and operableby the induction thereof, the How so induced being continuousldistributed and proportioned between primary fuel mixing means andsecondary mixing means, air control means for automaticallyproportioning the flow over a Wide range of running conditions,dampening means for said air control means, and fuel enriching means forsaid secondary mixing means responsive to rapid acceleration, said fuelenriching means being operable by said dampening means and comprising apair of pistons, one of which has a lost motion effect relative to theother.

2. In a fuel feeding system, for an internal combustion engine operableby the engine induction, a low level fuel tank, and a mixing nozzleoperated by the engine induction, said mixing nozzle including an airinlet and a fuel inlet, said latter inlet being circumferentiallydisposed to said former inlet and a secondary mixing nozzle adjacentsaid engine intake, said secondary nozzle including an air inlet and afuel inlet, said former inlet being tangentially disposed to said formerinlet so as to give a whirling movement at the point of intersection ofthe two inlets.

3. In a carbureting system for internal combustion engines, a fuelcontainer, means for causing the engine suction to act directly upon thefuel to lift the fuel from the container and means positioned eXteriorlyof the container for controlling the flow of fuel from the container soas to give the eectof a lift from a constant level in the container,said means comprising an inlet chamber open to the container, an outletchamber open to the reduced pressures below the intake manifold, adiaphragm forming a closure for said outlet chamber, a passagewayconnecting said chambers, a valve controlling said passageway, saidValve being seated on said dlaphragm.

4. In a carbureting system for internal combustion engines, a fuelcontainer, means for causing the engine suction to act directly upon thefuel to lift the fuel from the container and means positioned eXteriorlyof the container for controlling the flow of fuel from the container soas to give the effect of a lift from a constant level in the container,said means comprising an inlet chamber open to the container, an outletchamber open to the reduced pressures below the intake manifold, adiaphragm forming a closure for said Y outlet chamber, a passagewayconnecting said chambers, a valve controlling said passageway, saidvalve being seated on said diaphragm, said Valve normally closing thepassageway.

In witness whereof, I have hereunto signed my name.

GASPAR E. HOFBAUER.

